Reduced Oxygen Systems

The Physics of Fire: Working Principle

In order for a fire to start, as well as sustain, all elements including oxygen, heat and fuel, are mandatory. In the absence of any of these elements, it is impossible for a fire to ignite. Air in a normal atmosphere contains 1 molecule of oxygen for every 4 molecules of nitrogen. By altering this ratio, to 1: 6, a low oxygen environment equivalent to living in a hill station is created. Increased number of nitrogen molecules effectively block combustion from accessing oxygen molecules, not allowing fire to ignite or propagate. As a result of this process, oxygen concentration is reduced from 21% to 15%. This is also usually the percentage of oxygen maintained in an aircraft.

The operational Principle

  • Fresh ambient air is drawn in by the compressor, it passes through the dryers and becomes free of impurities when it passes through the filters.
  • In the air separation unit, oxygen enriched air (30% O2) is turned into low oxygen air (15%) by increasing the nitrogen content from 78 % to 85%.
  • The sensors installed in the room help monitor the oxygen level in the room and the control unit ensures a stable low oxygen environment.

Normal Air, Sea Level
Normobaric Normoxic Atmosphere

Normal Air, High Altitude
Hypobaric Normoxic Atmosphere

Low Oxygen Air, Sea Level Normobaric Hypoxic

Installation Example

  • portfolio


  • At 15.2% O2 by volume, Class A fires are extinguished, and at 14.3% O2 by volume, Class B fires are extinguished.
  • Common flammable solid materials & liquids cannot be ignited in environments where O2 content is lower than 16% at sea level barometric pressures

With the oxygen content in the air being reduced to lower than 16%, the flaming combustion access to oxygen is also reduced, i.e., the fire intensity is reduced from a 100% to 10%

Altair Reduced Oxygen System has been approved by European Safety Standards
  • A European Code EN: 16750 has recently been approved as late as September 2017
  • This presents an opportunity for us to leap to a next-generation fire prevention technology
  • Technology is included in National Building Code 2016 for E-2, E-3 & E-4
  • Technology included in recommendation issued by Fire Adviser, Govt. of India to Oil PSU’s for critical hydrocarbon applications
  • Additional standards approving this technology include:
    • International Mountaineering and Climbing Federation (UIAA),
    • The British Standards Institution (BSI) and
    • The Swiss National Accident Insurance Fund (SUVA).
    • UL
Risk Class O2 Concentration C% by volume Safety Measures Equivalent altitude m (approx.)
0 20.9% > c > 17.0%
  • Instruction of personnel only safety measure required.
  • Room can be permanently occupied.
0 – 1600m
1 17.0% > c > 15.0%
  • Medical examination
  • Instruction of personnel
  • After 4h, break of 30m outside the oxygen reduced area is required
1600 – 2500m
2 15.0% > c > 13.0%
  • Medical examination
  • Instruction of personnel
  • After 2h, break of 30m outside the oxygen reduced area is required
2500 – 3800m
3 c < 13.0%
  • Not covered in this annex
  • Entry without specific additional measures not permitted
> 3800m

Benefits over Conventional Flooding Systems

  • The safest way to fight a fire is to prevent it from starting. ROX system is the only technology that actually & surely prevents a fire from starting.
  • Unlike gas suppression systems, ROX Systems do not require cylinder replacement every 5 years.
  • It eliminates risk caused by un-tested systems.
  • There is no possibility of unintentional activation.
  • Nitrogen has excellent diffusion properties, therefore gas mix in the rooms is even. There is no possibility of asymmetric pockets, as may be the case with suppression based systems.
  • The nitrogen being introduced into the room has very low dew point. Additionally, gas is dried through desiccant, leading to overall reduction in RH%.
  • The ROX System is not cumbersome.
  • ROX System is optimized to low energy consumption.
  • Unlike, gas suppression systems ROX Systems do not release high acoustic noise (90 – 130 dB) on activation; which damages hard disk drives.

Areas of Application Rox Technology

  • Ordnance Depots
  • Hazardous & explosive Storage
  • Mission critical nfrastructure (above/underground)
  • Command & control centers
  • Sensitive laboratories & production areas
  • Data centers
  • Clean rooms
  • Mission critical manufacturing
  • Archives & document banks
  • Vaults